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Eye movements get re-enacted when we remember

An imaging and eye-tracking study has shown that the brain uses eye movements to help us recall remembered images.

A small study has tested the eminent Donald Hebb’s hypothesis that visual imagery results from the reactivation of neural activity associated with viewing images, and that the re-enactment of eye-movement patterns helps both imagery and neural reactivation.

In the study, 16 young adults (aged 20-28) were shown a set of 14 distinct images for a few seconds each. They were asked to remember as many details of the picture as possible so they could visualize it later on. They were then cued to mentally visualize the images within an empty rectangular box shown on the screen.

Brain imaging and eye-tracking technology revealed that the same pattern of eye movements and brain activation occurred when the image was learned and when it was recalled. During recall, however, the patterns were compressed (which is consistent with our experience of remembering, where memories take a much shorter time than the original experiences).

Our understanding of memory is that it’s constructive — when we remember, we reconstruct the memory from separate bits of information in our database. This finding suggests that eye movements might be like a blueprint to help the brain piece together the bits in the right way.

A study involving 18 volunteers who performed a simple orientation discrimination while on a stationary bicycle, has found that low-intensity exercise boosted activation in the visual cortex, compared with activation levels when at rest or during high-intensity exercise.

A small study that fitted 29 young adults (18-31) and 31 older adults (55-82) with a device that recorded steps taken and the vigor and speed with which they were made, has found that those older adults with a higher step rate performed better on memory tasks than those who were more sedentary.

The number of items a person can hold in short-term memory is strongly correlated with their IQ. But short-term memory has been recently found to vary along another dimension as well: some people remember (‘see’) the items in short-term memory more clearly and precisely than other people.

Spatial abilities have been shown to be important for achievement in STEM subjects (science, technology, engineering, math), but many people have felt that spatial skills are something you’re either born with or not.